1. Technical Field of the Present Invention
The present invention generally relates to the design automation of complex circuits to be integrated on a single semiconductor device. More specifically, the invention relates to the specific stages of semiconductor chip design tools and methodologies.
2. Description of the Related Art
There will now be provided a discussion of various topics to provide a proper foundation for understanding the present invention.
In recent years, the ability to design complex semiconductor devices has increased and it is quite common to observe designs with millions of gates all reduced to a single integrated circuit. Today's complex designs are combinations of acquired intellectual property (IP) in the form of logic design libraries such as logic gates, flip-flops, memories, etc., as well as more complex building blocks such as micro-controllers, digital signal processors (DSP), phase-locked loops and many others. Designers combine these design libraries with their self-conceived innovations and ideas, as well as with portions of designs that may have been previously used, to form new and more sophisticated solutions.
Referring to FIG. 1, the process of the design of a semiconductor device is illustrated, where the various stages of a design are shown. Commonly, a design is described in a hardware definition language (HDL), such as register transfer level (RTL). This enables the capturing of the design concepts in a manner that allows certain automated tools to handle the process of turning the design concepts into a transistor level solution required for the actual manufacturing of a semiconductor device.
An HDL representation 110 of a chip is prepared, at least partially based on the design representation 120 supplied for the purpose of designing the chip. It should be noted that the design representation 120 has certain constraints 170A. Constraints 170A define the ways that the design representation 120 may be used and such constraints ought to be at least partially taken into consideration as early as the HDL 110 stage of the design. Upon completion, or at least partial completion of the design, the verification stage 130 may begin. However, such verification must take into consideration various constrains 170B, which may be constraints imposed by the designer, the combinational use of the design representation 120 with the newly added designs, and other factors. If errors are detected, the HDL 110 must be corrected based on the errors found in this stage. Next, the synthesis stage 140 takes place, where the general logic design is further detailed in the transistor level. Additional constraints 170C are added at this stage, and may be constraints relative to the drive capability of transistors, speed requirements and similar parameters. If errors are detected, the HDL 110 must be corrected based on the errors found at this stage. These steps are similarly repeated at test stage 150 and the manufacture stage 160, adding constraints 170D and 170E that must be taken into consideration to ensure a successful and operative chip. At each such stage, upon detection of an error, the HDL 110 must be corrected and the process repeated. The compliance with the process is important as is the manufacturing costs of sophisticated devices which, when using deep sub-micron design rules, is extremely high. Moreover, additional design and manufacturing cycles are not only expensive but contribute to delays in introduction of products into the marketplace. It should be further noted that such complex devices are customarily designed by large groups of engineers of different backgrounds and geographical locations, further enhancing the design's vulnerability to errors.
It would be therefore advantageous to develop a system and a method that allows for easy collaboration between large groups of designers using multiple sources of design representation and design types. It would be further advantageous if there would be easy referencing between each stage of the design for quick identification and corrections of design errors.